CRED 40m Gridded bathymetry of the banktop and slope environments of Two Percent Bank (also called Tulaga Seamount), American Samoa (Arc ASCII Format)

Abstract:

Gridded (40 m cell size) bathymetry of Two Percent Bank (also called
Talaga Seamount) that lies between southeast of Tutuila, American Samoa,
South Pacific. Almost complete bottom coverage was
achieved in depths between 78 and 2221 meters. The bathymetry dataset
includes Simrad EM300 and EM3002 data collected during Feb. to March of 2006.

Supplemental_Information:

Data were collected aboard the NOAA Ship Hiialakai, a 218' United States
National Oceanographic and Atmospheric Administration research ship. The NOAA
Ship Hiialakai's survey sensors include a 30 kHz Simrad EM300 and a 300 kHZ
EM3002 sonar both of which provide bathymetry and imagery data,
a TSS/Applanix POS/MV Model 320, which measures position,
velocity, attitude and heading, and a Seabird SBE 9/11 plus CTD used to
measure sound velocity profiles. Sensor configuration for the Hi'ialakai for
cruise HI-06-02 is documented in the cruise/multibeam metadata file
HI0602_MB_Metadata.txt.

Planar coordinates are encoded using Row and Column
Abscissae (x-coordinates) are specified to the nearest 40
Ordinates (y-coordinates) are specified to the nearest 40
Planar coordinates are specified in meters

The horizontal datum used is D_WGS_1984.
The ellipsoid used is WGS_1984.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257224.

Depth values are real values based on the average of the
soundings that fell within the extracted grid cells. The number of
soundings per grid cell range from >1000 soundings in shallow depths
to as few as 20 soundings in deeper areas. A total error budget for
this survey has not been developed. Therefore, the accuracy of depth
measurements should be considered to be within 1 per cent of water depth.

The data were collected in support of Coral Reef Conservation Program goals
to map all shallow (0-30 m) coral reefs in US Pacific waters and priority
moderate (> 30 m) depth areas by 2009. The data are being used to provide
bathymetric and backscatter data for previously unmapped areas; in support
of ecosystem management requirements for benthic habitat mapping and
location of Essential Fish Habitat; and to study the geologic features of
the area.

Data are collected for resource management
and research purposes and are tested for internal consistency; however,
no effort is made to compare these data to external references or to
other published data.

These data are not to be used for navigation purposes.
Please acknowledge the NOAA Coral Reef Ecosystem Division,
Pacific Islands Fisheries Science Center and the Pacific Islands Benthic
Habitat Mapping Center, School of Ocean and Earth Science and Technology, University
of Hawaii as the sources of this information.

These data are not to be used for navigational purposes.
NOAA makes no warranty regarding these data, expressed or implied, nor
does the fact of distribution constitute such a warranty. NOAA cannot
assume liability for any damages caused by any errors or omissions in
these data, nor as a result of the failure of these data to function
on a particular system.